This center was originally funded in October 1991 through a NIDA initiative designed to create treatment evaluation centers. Evaluation strategies are based upon the assumption that the patient and treatment characteristics under study can be reliably, validly and sensitively measured. Therefore, the basic measures and instruments that are employed in treatment evaluation studies are the foundation of our knowledge about the effects of treatments. Because of the importance of measurement accuracy and appropriateness in evaluation research we have created a center dedicated to the development, testing and dissemination of evaluation instruments, methods and measures: the Instrument and Methods Development Center (IMDC). We have focused the efforts of this center in two areas: 1) Identification of Measurement Needs Within the Treatment Evaluation Field - This is an extension of our ongoing efforts to determine the important evaluation needs of the treatment field and then to develop functional instruments and methods to meet those needs. 2) Servicing the Measurement Needs of Other NIDA Treatment Evaluation Researchers and Centers - An explicit goal of our work for the next five years will be to use the expertise and resources developed here to work collaboratively with other NIDA centers and investigators in the development and parametric testing of their instruments and methods. The Core section of the proposal is organized as follows: I. The Work Accomplished Section contains a description of our work over the past four years in developing and testing treatment evaluation instrument and methods. A. Development of Evaluation Instruments and Methods B. Publication and Information Dissemination II. The Administration Organization Section describes the administrative functions and core personnel of the proposed Center and describes the day-to-day plans for its operation. A. Administrative Coordination B. Scientific Review and Guidance C. Education and Professional Training III. The Quality Assurance Section describes the standardized procedures we have introduced to assure reproducibility and accuracy of findings. A. Subject Recruitment B. Interviewer Training C. Project Coordination Across Studies and Sites D. Quality Assurance Procedures for Data Collection E. Quality Assurance Procedures for Urine Toxicology F. Quality Assurance Procedures for Data Management IV. The Pilot Projects Section describes six potential projects that we plan to pursue in the coming period of funding